1. Field of the Invention
The present invention relates to a photosensitive transfer material suitable for dry transfer onto a substrate having unevenness and to an image forming method using the same. A photosensitive transfer material and an image forming method according to the invention are preferably used in production of a color filter employed in a liquid crystal display or the like and in production of a printed circuit board.
2. Description of the Related Art
A photosensitive transfer material for transferring a photosensitive resin layer onto a substrate is well-known (for example, see Japanese Patent Application Publication (JP-B) No. 56-40824). Such a photosensitive transfer material is used in production of printed circuits, intaglio printing/relief printing plates, name plates, multicolor trial printing samples, offset printing plates, screen printing stencils and the like. The transfer material is constructed of at least a temporary support, an intermediate layer and a photopolymerizable layer. A substrate is adhered to the transfer material at the photopolymerizable layer, and then only the temporary support is peeled off. Thereafter, light is exposed through a separation layer, followed by developing, to form an image on the substrate. The separation layer plays a role of oxygen blocking, and it is advantageous with respect to exposure to light in the air. A thickness of the separation layer is very thin, having a value of the order from 0.5 μm to 5 μm; therefore, no problems occur from the point of view of resolving power, either.
For example, Japanese Patent Application Laid-Open (JP-A) No. 5-173320 discloses a photosensitive transfer material, in which an alkali-soluble thermoplastic resin layer, an intermediate layer and a photosensitive resin layer are provided in this order on a temporary support. However, in the above-mentioned photosensitive transfer material, it is impossible to transfer only the intermediate layer and the photosensitive resin layer, and the thermoplastic resin layer is also transferred simultaneously, inevitably causing developing solution to be wastefully consumed.
Moreover, for example, Japanese Patent Application Laid-Open (JP-A) No. 4-12980 discloses a method of transferring a photosensitive resin layer, the method employing a photosensitive transfer material constructed of a thermoplastic resin layer, a separation layer and a photosensitive resin layer provided in this order on a temporary support, particularly a plastic film having a gelatin undercoat thereon. The photosensitive resin layer is adhered onto a support, and thereafter the temporary support and the thermoplastic resin layer are simultaneously peeled-off and removed to thus transfer the photosensitive resin layer onto the support. In this method, it is not always easy to control peelability between the thermoplastic resin layer and the separation layer. Moreover, the method is not sufficient to satisfy requirements for automation of a peeling operation.